9bd9590767
Previously we would write to class/style as strings `element.className` and `element.style.cssText`. Turns out that approach is good for initial render but not good for updates. Updates using this approach are problematic because we have to check to see if there was an out of bound write to style and than perform reconciliation. This also requires the browser to bring up CSS parser which is expensive. Another problem with old approach is that we had to queue the DOM writes and flush them twice. Once on element advance instruction and once in `hostBindings`. The double flushing is expensive but it also means that a directive can observe that styles are not yet written (they are written after directive executes.) The new approach uses `element.classList.add/remove` and `element.style.setProperty/removeProperty` API for updates only (it continues to use `element.className` and `element.style.cssText` for initial render as it is cheaper.) The other change is that the styling changes are applied immediately (no queueing). This means that it is the instruction which computes priority. In some circumstances it may result in intermediate writes which are than overwritten with new value. (This should be rare) Overall this change deletes most of the previous code and replaces it with new simplified implement. The simplification results in code savings. PR Close #34804 |
||
---|---|---|
.. | ||
bazel | ||
bazel-schematics | ||
cli-hello-world | ||
cli-hello-world-ivy-compat | ||
cli-hello-world-ivy-i18n | ||
cli-hello-world-ivy-minimal | ||
cli-hello-world-lazy | ||
cli-hello-world-lazy-rollup | ||
dynamic-compiler | ||
hello_world__closure | ||
hello_world__systemjs_umd | ||
i18n | ||
injectable-def | ||
ivy-i18n | ||
language_service_plugin | ||
ng_elements | ||
ng_update | ||
ng_update_migrations | ||
ngcc | ||
platform-server | ||
service-worker-schema | ||
side-effects | ||
terser | ||
typings_test_ts36 | ||
typings_test_ts37 | ||
.gitignore | ||
README.md | ||
_payload-limits.json | ||
check-dependencies.js | ||
get-sharded-tests.js | ||
run_tests.sh |
README.md
Integration tests for Angular
This directory contains end-to-end tests for Angular. Each directory is a self-contained application that exactly mimics how a user might expect Angular to work, so they allow high-fidelity reproductions of real-world issues.
For this to work, we first build the Angular distribution via ./scripts/build-packages-dist.js
, then
install the distribution into each app.
To test Angular CLI applications, we use the cli-hello-world-*
integration tests.
When a significant change is released in the CLI, the applications should be updated with
ng update
:
$ cd integration/cli-hello-world[-*]
$ yarn install
$ yarn ng update @angular/cli @angular-devkit/build-angular
$ yarn build
$ yarn test
Afterwards the @angular/cli
and @angular-devkit/build-angular
should be reverted to the file:../
urls
and the main package.json
should be updated with the new versions.
Render3 tests
The directory cli-hello-world-ivy-compat
contains a test for render3 used with the angular cli.
The cli-hello-world-ivy-minimal
contains a minimal ivy app that is meant to mimic the bazel
equivalent in packages/core/test/bundling/hello_world
, and should be kept similar.
Writing an integration test
The API for each test is:
- Each sub-directory here is an integration test
- Each test should have a
package.json
file - The test runner will run
yarn
andyarn test
on the package
This means that the test should be started by test script, like
"scripts": {"test": "runProgramA && assertResultIsGood"}
Note that the package.json
file uses a special file:../../dist
scheme to reference the Angular
packages, so that the locally-built Angular is installed into the test app.
Also, beware of floating (non-locked) dependencies. If in doubt, you can install the package
directly from file:../../node_modules
.
WARNING
Always ensure that
yarn.lock
files are up-to-date with the correspondingpackage.json
files (wrt the non-local dependencies - i.e. dependencies whose versions do not start withfile:
).You can update a
yarn.lock
file by runningyarn install
in the project subdirectory.
Running integration tests
$ ./integration/run_tests.sh
The test runner will first re-build any stale npm packages, then cd
into each subdirectory to
execute the test.